Add plugin.info.txt

Remove getInfo method from plugin.
Update mail address.
Update README

Move to markdown
Move INSTALL instructions to README.
Update description.
Update Javascript to use jQuery

Plugin is now compatible with "Adora Belle" and following releases.
Change mail addresses.
Reference toolbar icon directly instead of needing a copy.
Update picker icon to be transparent

Rather hackish - I just removed the white areas. Maybe someone can
contribute a new icon.